(1) Field of the Invention
The present invention relates to a network hardware device establishing a connection with a network, and including a computer or a controller capable of executing processing based on data transmitted from the network.
(2) Description of the Related Art
Due to improved communication performance of a network, a network hardware device performing data communication becomes insufficient in processability, so that a function other than the data communication of the network hardware device is degraded. Herein, the network hardware device refers to a device functioning as a home appliance such as a DVD recorder or a television set and, also, functioning as a network. If the function other than the data communication is degraded, the network hardware device fails to function as a home appliance in some cases. This case is inappropriate. In order to prevent the aforementioned disadvantage, therefore, the network hardware device adopts polling so as to execute processing at regular intervals.
On the other hand, as disclosed in JP2002-538550A, a computer without a function of a home appliance has the following configuration. A host computer or a host controller (a host CPU) executing processing based on data transmitted from a network reduces frequency of reception interrupt by the network by using a timer. A reception packet counter counts up received packets. As a result of confirmation using a threshold that packets in predetermined number are transmitted since previous reception interrupt, reception interrupt is occurred. Thus, overflow in a reception buffer can be prevented and all pieces of received data can be subjected to processing efficiently.
However, the conventional method using a timer and a threshold based on count of received packets has the following problem. If many packets each having a small data size are received, interrupt by arrival of a packet count threshold is occurred frequently at an interval shorter than a preset interval. Consequently, in a host CPU, a function of a home appliance is out of control or processing is delayed.
On the other hand, polling has the following problem. A host CPU must confirm reception of data. Consequently, a function of a home appliance is degraded even when no data is received.